Compound engine



7 Sheets-Sheet l Filed NOV. 22, 1954 BY -SWV A HUP/V5 Y Aug. 30, 1960 R.s. RAE

coMPouNn ENGINE 7 Sheets-Sheet 2 Filed NOV. 22, 1954 F/ Ef 2 INVENTOR.

BY /Z WW FTE. 5

Aug. 30, 1960 R. s. RAE

COMPOUND ENGINE 7 Sheets-Sheet 3 Filed Nov. 22, 1954 INI/ENTOR BY CLAWAug. 30, 1960 R. s. RAE

COMPOUND ENGINE 7 Sheets-Sheet 4 Filed NOV. 22, 1954 INVENTOR.

BY gv W Aug, 30, 1960 R. s. RAE 2,950,593

COMPOUND ENGINE Filed Nov. 22, 1954 '7 Sheets-Sheet 5 a BY ArroRA/fr R.S. RAE

COMPOUND ENGINE 7 Sheets-Sheet 6 Filed NOV. 22, 1954 /P/m/am/f JAM/a/54/5,

INVENTOR.

BY KWMJ Aug. 30, 1960 R. s. RAE

coMPoUND ENGINE 7 Sheets-Sheet '7 Filed Nav. 22, l1954 INVENTOR.

Afro/mfr FAA/00L PH SAMU/EL R45,

CoMPoUNn ENoiNE Randolph Samuel Rae, Santa Monica, Calif., assigner toThe Garrett Corporation, Los Angeles, Calif., a corporation ofCalifornia Filed Nov. 22, 1954, Ser. No. 470,238

9 Claims. (Cl. Gil-35.6)

This invention relates to a compound engine which is powered by anon-air breathing power source and by the combustion of atmospheric airtaken into the engine, and more particularly to an engine in the whichthe nonair breathing power source is connected to the compressor for theengine.

Present types of turbo prop engines and turbo jet engines utilize a.compressor to compress the entering air and a combustion chamber isprovided for burning this compressed air to increase its temperature andpressure. The products of combustion drive a turbine which is directlyconnected to the compressor and this turbine exhausts to atmosphereproducing a jet thrust. In turbo prop engines, the propeller is alsodriven by the turbine whereas in a pure turbo jet type of engine, theturbine rives only the compressor. At high altitudes, these engines mustexert a considerable amount of power on the atmospheric air in order toobtain a sufficiently high discharge pressure from the compressor forcontinued combustion in the combustion chamber and to prevent flame-out.Thus, the celing of these present type engines is limited because of thefact that suicient high pressure air cannot be supplied to thecombustion chamber.

By the present invention it is proposed to drive the compressor ofeither a turbo prop or a turbo jet engine by a non-air breathing enginesuch as disclosed in pending U.S. Application Serial No, 417,867 ledMarch 22, 1954 by Randolph Samuel Rae and entitled Non-Air Breathingengines. Any suitable type of liquid or gas can be utilized by theengine as fuel such as liquid hydrogen, gasoline, methane, acetylenealcohol and the like and the fuel can be combusted by any suitableoxidant, such as air, oxygen, hydrogen peroxide, nitric acid, etc. ineither the liquid or gaseous phase. Both the fuel and the oxidant can becarried in separate tanks in the mounting craft for the engine andsupplied to the engine in the desired ratio. Since the non-air breathingcomponent of the present invention is directly connected to thecompressor, theY power transmitted to the compressor is independent ofthe atmospheric pressure and higher pressure ratios can be obtained athigh altitude in order to raise the maximum ceiling which can beobtained before dame-out occurs. ln addition, an excess of fuel issupplied to the non-air breathing engine as a diluent so that theexhaust from the engine is still rich in fuel, and this exhaust can beutilized in a combustion chamber supplied with atmospheric air in orderto produce high temperature products of combustion for driving theturbine. This turbine can be directly connected to both the compressorand the propeller as in a turbo prop engine or can be solely connectedto the compressor as in a turbo jet engine. Also, a certain amount ofthe fuel in the exhaust from the non-air breathing engine can betransmitted to an afterburner located aft of the turbine in order toobtain additional thrust by burning part of the exhaust gases in theafterburner. When low ternperature hydrogen and oxygen are utilized asthe fuel and oxidant, respectively, for the non-air breathing engine, it

r'ice is possible to have a high percentage of unburned hydrogen fuel inthe exhaust from the engine together with some steam. Various types ofnon-air breathing engines can be utilized with the invention and can bemade very small for the required output so that such an engine can belocated within the duct of the compound engine. It will be understoodthat the compound engine of this invention is capable of delivering morepower per unit Weight of fuel than prior types of engines and that thecompound engine operates more eiciently.

It is therefore an object of the present invention to provide a compoundengine in which a non-air breathing component is utilized to drive acompressor and the exhaust from this nonair breathing engine is utilizedby a combustion chamber to burn atmospheric air and drive a turbine.

Another object of the present invention is to provide an enginecomponent for driving a compressor, which component is independent ofatmosphere so that higher pressure ratios can be obtained at highaltitudes.

A still further object of the present invention is to provide a turbojet engine in which the compressor is driven by a non-air breathingengine and by a turbine which is driven by the combustion productsresulting from combustion of the exhaust from the non-air breathingengine.

Another object of the invention is to provide a turbo prop engine inwhich the compressor is driven by a nonair breathing engine and theexhaust from the non-air breathing engine is combusted to drive aturbine connected to both a compressor and a propeller.

These and other objects of the invention not specically set forth abovewill become readily apparent from the accompanying description anddrawings in which:

Figure l is a side elevational View of the turbo prop form of theinvention with parts cut away in order to show the non-air breathingengine connected to the compressor and the turbine connected to both thecompressor and the propeller.

Figure 2 is a transverse vertical section along line 2 2 of Figure 1showing the construction of the compressor.

Figure 3 is a transverse vertical section along line 3 3 of Figure 1illustrating the construction of the turbine.

Figure 4 is a transverse vertical section along line 4 4 of Figure lshowing theY manner in which the exhaust from the engine is conducted tothe various combustion chambers and also illustrating the air intakepassages for the engine.

Figure 5 is a horizontal section along line 5 5 of Figure 1 showing theconstruction of the combustion chambers.

Figure 6 is a vertical section along line 6 6 of Figure l showing theconstruction of the afterburner which is connected to the exhaustmanifold of the non-air breathing engine.

Figure 7 is a vertical section along line 7 7 of Figure 6 showing one ofthe flame holders for the afterburner.

Figure 8 is a side elevational View of the turbo jet form of theinvention with parts cut away in order to show the compressor, theturbine, and the non-air breathing engine component.

Figure 9 is an end elevational view along line 9 9 of Figure 8 showingthe exhaust passages from the nonair breathing engine to the manifoldfor the combustion chambers.

Figure 10 is a vertical section along line 10-10 of Figure 8 showing theconstruction of the compressor for the turbo jet form of the invention.

Figure 11 is a diagrammatic view of the cycle for one Y 3 form ofnon-air breathing engine which can be utilized in the invention.

Referring to the turbo prop form of the invention Aillustrated in Figurel, the compound lengineis comprised of av plurality ofcasing sections15,16, 17, 18 and 19 positioned successively from the forward end of theengine and secured togetherby bolts 20. The section 17 has an extension21 in the form of an internal cylindrical member which supports thenon-air breathing engine 22, the construction of which will be laterdescribed.

The drive shaft of theV engine 22 carries gear 23 which meshes with gear24 in orderV to drive cylindrical shaft 25. The shaft 25 is mounted by abearing 26 which is retained by member 27 connected to the extension 21and by ring 28. A sealing memberl 29 is secured to the member` 27 bybolt 30 and serves to retain ring 28. The shaft '25 is also supported bybearing `31 which is retained by extension32 of casing section 17 and bya ring V33. A sealing member 34 is secured to extension 32 by 25 at aposition between bearings 26 and 39 and each of these hubs carry a rowof compressor blades 44 which cooperate with rows of stationary blades45 carried by casing section 15 (see Figure 2). The rotation of thecompressor blades serves to increase the pressure of the air enteringthe engine through the casing section 15 and around the member 36. Thecompressor wheels 43 are surface for the incoming air.` As illustratedin Figure 2, the casing section 15 is split in order tov permit easyassembly by means of bolts 46.

' The air compressed by the compressor blades 44 enters passages 47, 48and '49 which are formed between extension 21 and casing sections 16 and17 Vand which are separated by the partitions 51, 52 and -53 V(seeFigure 4). The three passages 47, 48 and 49 terminate in a chamber 54formed in casing sections 17 and the chamber has a plurality of openingseach of which receives the end of an outer chamber 55' for a combustionchamber 56. Six such combustion chambers are equally spaced around thecircumference of the engine and are held in position by flange 57 ofsection 17 and ilange 58 of section 16. An inner chamber 57 ispositioned within each of the 'combustion chambers 56 and extends toconnect with passage 58 formed in casing section 17. A plurality ofopenings 59 are positioned in the forward end of each :inner casing 57so that the air entering the chamber 54 from passages 47, L48 and 49passes to the forward end of the innerrchamber 57 and through theopenings 59.

Y' The exhaust from the non-air breathing engine 22 is `Vled through apassage 60 formed in partition 53 to a 'manifold 61 formed in casingsection 16. Manifold 61 is circular in form in order to supply theexhaust from the non-air breathing engine to each of the combustion-chambers through a passage 62, which leads through outer chamber 55 tothe interior of inner chamber 57 (see` Figure The passage 62 terminateswithin chambei' 57 in a convergent-'divergent section 63 and thedivergent portion contains a wire screen 64 for supporting a catalystwhich serves to maintain the combustion of the gaseous fuel enteringfrom passage 62 with the -interlocked at their ends in order to form asmooth ow and 66 in order to seal the open end of the shaft 2.5. Thus,both the turbine Wheel 67 and the non-air breathing engine 22 areconnected to the shaft 25 in order to -drive the compressor blades 44.

A shaft 73 is positioned vm'thin the hollow shaft 25 and is mountedconcentrically with the shaft by bearings 74 and 75 located at oppositeYends of the shaft 25. The rear end of the shaft 73 is also supported bybearing 76 which is positioned by a projection 77 and by a ring 80. T heprojection 77 is'supported by av conical member 73 which is positionedin the aft end of the engine by struts 79 secured to casing section 19.A sealing member 81 is secured to projection 77 by a boltl82 and servesto retain ring 80. Also, an end plate 83 is secured to projection 77 andan'oil agitation 84 is located between th'e end plate and the bearing76.

A turbine wheel 85 is secured to shaft 73 by hub members 86 and 87 andthe wheel ,85 carries two rows of blades 88 and ,8,9 which cooperatewith stationary rows of blades 90 and 91, carried bypcasing section 18.The turbine wheels67 ,and 85 and conical member 78 form the passage 93Vwhich leads to the exhaust opening 94 located yat the aft end of theengine. The forward end of the shaft 73 projects through cylindricalmember 36 and connects with a hub' 95 of a propeller 96 (not shown).Thus, it yis apparent that the turbine wheel 85 serves to drive thepropeller 96 vthrough shaft 73 which passes through the compressor shaft25.' The sealing members 81and 34 and the end plate 83 serve to confinethe driving fluid for wheels 67 and 85 and member 72 serves to preventthis fluid from entering Vshaft 2.5. Also the sealing members 29 and 38conline the driving lluid for the compressor. o

An afterburner is located within the section 19 and comprises a circularV-shaped support ring 98 which passes around the conical member 78 (seeFigure 6) and this ring is secured in position by a plurality of struts99. Six arne holders 100 are evenly spaced around the ring 98 and are inthe formrof a conical sectiong101 which supports a screen 102. Fuel issupplied to` each of the flame holders through a passage 103 whichterminates in a jet 104 within the conical section 101 and the jet isdirectedagainst a catalyst 105, such aslinely divided platinum,deposited von the wireV screen `102. Each of the passages 103 connectswith `a longitudinal passage 106 located exteriorly of the engine. Eachpassage 106 leads to the manifold 61 and contains-a valve 107 to controlthe amount offuel flowing to each of the flame holders. An electrical`ignition device of Well known Aconstruction (not shown) is provided Yforeachof the yfuel'tanle108is connected tov outer; chamber 109 of heatexchanger 110. by passage K1x11 and combustion chamber 112 is connectedto outer chamber 109 by passage 113.V The tank .108 contains asuitable'fuel, such as hydrogen, gasoline, methane, acetelyn, alcohol orthe like, either in the liquid or gaseous state. The fuel can be storedat a high pressure within tank 108 in order to obtain a high efficiencyin the working cycle of the engine. A separate tank 114 is utilizedtocarry the oxikdant for the engine and the tank is connected to outerchamber 115 of heat exchanger 116 through passage 117. The combustionchamber y112 is connected toouter chamber 115 by a passage 118 and apassage`119containing a valve for regulating the V-amount of oxidantsupplied to the combustion chamber. Any suitable oxidant, such asoxygen, hydrogen peroxide, nitric acid, etc. can be lutilized in eitherthe liquid or gaseous phase and can be held at a Ihigh pressure in tank114 to-increase the efficiency of the engine. When liquid fuel andoxygen are used, both will be vaporzed before entering the combustionchamber by heat exchangers 110 and 116 respectively, and the amount ofoxidant passing to combustion chamber 112 will be controlled by valve120 so that the temperature of the gases leaving the combustion chamber1.12 will be the maximum that can be Withstood by the constructionmaterials of the first stage. The combustion chamber 112 is connected bya passage 121 to the rst expansion stage 122 and the passage 121 willcontain both gaseous fuel and the by-products of the combustionreaction. For instance, when liquid hydrogen is utilized as the fuel andliquid oxygen as the oxidant, the passage 121 will contain both hydrogenand steam resulting from combustion of part of the hydrogen, whereas ifa hydrocarbon is utilized as the fuel, the passage 121 will contain anamount of hydrocarbon plus various combustion products, such as carbondioxide, carbon monoxide and steam.

First stage 112 of the engine will exhaust at a lower temperaturethrough a passage 123 to a second combustion chamber 124. and aregulated amount of oxygen will be led to combustion chamber 124 frompassage 118 through passage 125 and valve 126. In combustion chamber124, some more of the fuel will .be ignited with suicient oxidant toraise the temperature in passage 127 to that which can be withstood bythe second expansion stage 128 of the engine and the combustion chamber124 will reduce the amount of fuel and increase the -amount ofcombustion products. The stage 128 exhausts through passage 129 to athird combustion chamber 130 and the expansion of the gases throughstage 128 results in a lower temperature in passage 129. Additionaloxidant is added to the combustion chamber 130 from passage 118 througha passage 131 and valve 132 and the amount of oxidant is controlled byvalve 132 so that the temperature in passage 133 leading from thecombustion chamber 130 will be raised until it is at a temperature whichcan be withstood by the third expansion stage 134 of the engine. Thestage 134 exhausts to passage 135 which passes through inner chambers136 and `137 of heat exchangers 116 and 119, respectively, to increasethe temperature of the oxidant entering heat exchanger 116 and of thefuel entering heat exchanger 110.

Any number of stages can be added to the engine, such as stage 136having a combustion chamber 137, and oxidant can be supplied to thecombustion chamber 137 from passage 118. In general, a practical numberof stages can be utilized so as to obtain a reasonable compromisebetween the specific fuel consumption and the mechanical complexity forthe particular application under consideration. The temperature ofV thegases leaving the combustion chamber is regulated by the amount ofoxidant supplied to the combustion chambers through valves `121), 126and 132. It is not necessary that fuel and oxidant be at `a highpressure in tanks 108 and 114 respectively since pumps can be added tothe passages 111 and 117 in order to increase the pressure in thesepassages leading to the heat exchangers 110 and 116, respectively. Whileeach stage is illustrated as being an expansion turbine, it isunderstood that any one or the stages could consist of any othersuitable type of power producing unit, such as an expansion type gasengine. The non-air breathing engine 22 thus operates independently ofthe atmosphere since the engine carries its own fuel and oxidant supplyand each stage of the engine operates at as high a temperature aspossible in order to obtain maximum eiciency for each stage.

The operation of the turbo prop form of the invention d 40 percent) andthe steam resulting from the combustion of the other portion of thehydrogen gas. The non-air breathing engine 22 will drive the compressorblades 44 through the shaft 25 and since the engine 22 operatesindependent of the atmosphere, it is 4apparent that a large amount ofpower is available for the compressor in order to compress the incomingair to a high pressure regardless of the low atmospheric pressuresencountered will now be described and, for purposes of description,

the non-air breathing engine will be supplied with liquid hydrogen asfuel and with liquid oxygen as the oxidant. The non-air breathing engine22 is adjusted so that the exhaust from the engine through passage 60will contain.

at high altitudes. The exhaust in passage 60 enters manifold 61, and aportion of the exhaust is led to each of the combustion chambers 66Where the hydrogen gas is combusted within the combustion chamber withthe high pressure air in passage 47. The high pressure, high temperaturecombustion products leaving each of the combustion chambers throughpassage 58 serve to drive the turbine wheels 65 and 85 and the exhaustfrom these turbines is discharged through opening 94 in section 19 inorder to produce a jet thrust for the aircraft. The expansion of thecombustion products drives the turbine Wheel 67, which is connected toouter shaft 25 in order to aid the non-air breathing engine 22 anddriving the compressor blades. The rotation of turbine wheel by theexpansion of the combustion products drives the inner shaft 73 in orderto power the propeller 96. A regulated amount of exhaust from engine 22can be led to the flame holders of the `afterburner through the passages106 in order to burn a portion of the hydrogen gas in manifold 61 andprovide increased jet thrust from the opening S14. rl`hus, the turboprop form of the invention is suitable for high altitude operation sinceit utilizes separate fuel and oxidant supplies for the engine 22 so thatthis engine operates independently of the surrounding atmosphere. Thenon-air breathing engine 22 serves solely to drive the compressor andthe combustion chambers burn the exhaust from this engine withcompressed air to produce jet thrust and power for the compressor andpropeller. The only oxidant supply that need be carried by the aircraftis that needed by the non-air breathing engine 22. Therefore, theinvention provides a compound engine which utilizes a non-air breathingengine and combustion chambers located between the compressor and theturbine Wheels.

Referring now to the turbojet form of the invention illustrated inFigure 8, this form of the invention has casing sections 149, 141, 142,143 and 144 which are all secured together by bolts 145. A non-airbreathing engine 146 is located within a nose section 147 which issupported from casing section 148 by four struts 14S, each of whichcontains a passage 149 leading through the section 141i and connectingwith a manifold 150. The passages 149 serve to collect the exhaust fromthe non-air breathing engine 146 and supply this exhaust to the manifold150.

A conical member 151, similar in shape to conical member 78 of the rstform of the invention is supported Within casing section 14.4 by meansof struts 152 and the space between the member 151 and casing 144provides a passage 153 leading to the end opening 154. A shaft 155 iscentrally located within the engine and has one end connected to thenon-air breathing engine 146. This end of the shaft 8 is supported by abearing 156 which is positioned by a member 157 secured to the nosemember 147 and sealing member 15S helps to retain the bearing. The otherend of the shaft is supported by a bearing 159 positioned by anextension 160 from the conical member 151 and sealing member 161 servesto retain this bearing. The shaft is `also supported intermediate itsends by a bearing 162 positioned by an extension 163 from casing section142 and the casing section also carries a sealing member 164. Inaddition, a bearing 165 is supported by an extension 166 secured toextension 163 and the member 166 carries -fa sealing member 167.

A plurality of compressor hubs 168 are secured to the a high percentageof unburned hydrogen gas (such as 75 shaft 155 between the bearings 156and 165 and each of 'through openings 178.

ber 175 of each of six combustion chambers 176 and an inner chamber 177is positioned within each of the outer chambers 175 and contains a.number of openings 17S. Each of the inner containers 177 is alsoconnected through 'a passage 179 to the manifold 150 which receives theeX- haust from the non-air breathing engine 146. Each passage 179terminates in a converging-diverging section similar to section Y63 ofFigure 5 and the combustion chambers'maintain the combustionYV of theexhaust gases with the compressed air which enters the chambers The hightemperature, high pressure gasfrom the combustion chambers 176 entersspace 180 which contains `a 'row of'stationary blades 181 supported bycasing section 142. A second row of stationary blades 182 are carried bythe casing section 143 and these stationary blades 181 and 182 cooperatewith rows of rotating blades 183 and 184 carriedY by the turbine wheel185 which is secured by members 186 and 187 to the shaft 155. After thegases in the combustion chambers 176 pass through the turbine blades,the gases are exhausted out of nozzle Vopening 154 in order to providejet thrust for the aircraft. An afterburner is located within thepassage 153 V.and is formed of annular V-shaped ring 188 which supportssix cone members 189, each-containing a screen having a catalystdeposited thereon in the same manner as shown in Figure 7. Each of thecone members 189 is connected with the manifold 150 through a passage190 which contains a valve 191 to regulate the amount of fuel passingfrom the manifold 150 to the afterburner. It is understood that thecombustion chambers 176 and the non-air breathing engine 146A'oan be ofthe same construction as described in connection with the combustionchambers 56 and non-air breathing engine 22 of the rst form of theinvention and that the .physical form of the afterburner is identicalwith the afterburner of theV first form. An end plate 192 secured toextension 160 and serves to seal olf the end of the shaft 155 whichcarries an oil agitator 193. f

Referring now to the operation of the second form of Vthe invention, thenon-air breathing engine 146 operates upon -a liquid fuel supply and aliquid oxygen supply,

such as hydrogen and'oxygen, respectively. Within this engine, -aportion of the hydrogen is combusted in order Vto Vdrive thel compressorblade 169 independently ofthe surrounding atmosphere.V The exhaust fromthis engine contains a high percentage of unburned fuel, vsuch asVaboutY forty percent, together with steam resulting lfrom combustion ofthe other part of the hydrogen and the exhaust passesV to manifoldthrough passages 149. The exhaust in manifold 160 containing hydrogenfuel, is led to combustion chambers 176 where the fuel is ignited withthe compressed air from chamber 173. The high temperature, high pressuregas leaving the combustion chambers serves to drive the turbine wheel185 which is connected to shaft 155 and aids the non-air breathingengine 146 in driving the compressor blades Vto compress the enteringair. The gases leaving the blades of the turbine wheel 185 exhaust athigh pressure from opening 154 in order to provide the jet thrust forthe aircraft. Since the fuel and oxidant for the non-air breathingengine are carried separately within the vehicle, the non-air breathingengine will drive the compressor independently of the surroundingatmosphere and will produce a high compressor output .even at very highaltitudes where Vlowpressure atmospheric air is present...

8 Thus, sucient high'pressure can be supplied to the combustion chambersfor ignitng the vhydrogen fuel `in the exhaust from`the non-airbreathing engine and the total thrust Yof the engine will be developedby the combustion of the hydrogen with the compressed air. Aregulatedpor'tion'of the fuel Vin manifold 150 will be supplied to theafterburner in order to increase the jet Ythrust of .the engine'n awell-known manner.

YIt is understood thatY the passage 135 of the non-air breathing engineconnects with passage 60 in the first form of the invention and withpassages 149 in the second Vform of the invention. In both lforms of theinvention, `an excess of fuel issupplied through passage 113 of thenonfair breathing engine so Vthat not all of the fuel is .combusted vinthe engine 'anda quantity of uncombusted Vfuel is receivedby passageV13:5. Also, in both forms of the invention, thek output-shafts o'f allstages of the nonair breathing engine are connected together to drivethe shaft for the compressor.

By the present invention, a compound engine is provided in which thecompressor is driven by a non-air breathing engine to'obtain a highdischarge pressure from the compressor for continued combustion in thecombustion chambers at high 4altitudes where prior types of Vjetengnes'dq not develop sulicient power to produce the discharge Ypressurerequired' to prevent flame-out. Since a very high power output can beobtained from a 'non-air breathing engine of very small size, it isconvenient to locate the engine within the duct of the compound engineand directly connect it to the compressor. VWhile one form ofvnon-airbreathing engine has been described for purposes of illustration, it isunderstood that other types of such engines can be utilized and suit-.able fuel and oxidant storage means can be associated with the engine.Also, the engine can be operated either It is understood that compressorand turbine construction illustrated can be varied in any well-knownmanner. Since the power delivered to Vthe compressor by the non-airbreathing en- Ygine isindependent of atmosphere, high pressure ratioscan Ybe obtained by the present invention at high altitudes and thusthe'maximum ceiling of the aircraft can be raised before flame-outoccurs. Various other modications are contemplated by those skilled inthe art without departing from the spirit and vscope of the invention-as hereinafter defined by the appended claims.

What is claimed is:

1. A compound engine for propelling an aircraft comprising a casingdefining a fluid passage having an exhaust opening, Vcompressor meanslocated in the forward Y portion of said casing for compressing airentering said passage'and turbine means connected with said compressorVmeans and locatedY rearwardly thereof in said casing, combustionchamber means located in said uid passage between said compressor meansand turbine means and utilizing compressedrair from said compressormeans to maintain combustion therein, and a non-air breathingV enginelocated within said casing and having separateV fuel and oxidantsupplies carried byV said aircraft, said non-air breathing engine beingconnected to said Vcompressor means to continually drive said compressormeans during ight independently of the atmos- Yphere Vto increase theefficiency of said engine and probusted fuel being the sole fuel sourcefor said combustion chamber means.

3. A compound engine as dened in claim 2 having afterburner meanslocated behind said turbine means and means for connecting the exhaustfrom said non-air breathing engine with said afterburner means so that apart of the uncombusted fuel in the exhaust can be combusted in saidafterburner means.

4. A compound engine as defined in claim 1 having propeller meanslocated at the forward end of said casing, said turbine means having oneportion connected to said propeller means and another portion connectedto said compressor means, said propeller means and the liuid exhaustingfrom said opening being operable to jointly propel said aircraft.

5. A compound engine as defined in claim 1 wherein said non-airbreathing engine comprises a plurality of stages supplied from secondcombustion chamber means, said fuel and oxidant supplies being combustedwithin said second combustion chamber means and the products ofcombustion being supplied to each stage at a temperature which can bewithstood by each stage.

6. A compound power unit for propelling a vehicle in the atmospherecomprising a casing deiining a through uid passage having an exhaustopening, compressor means located within said casing for compressingatmospheric air entering said casing, a non-air breathing engineconnected to said compressor means for continually driving saidcompressor means, separate supplies of fuel and oxidant carried by saidvehicle for use by said engine, said engine having first combustionmeans wherein only a portion of the fuel supplied to said engine iscombusted with said oxidant, turbine means located within said casingand connected with said compressor means, and second combustion meanslocated within said casing between said compressor means and saidturbine means and connected with the fuel-rich exhaust from said engineand with the compressed air from said compressor means, the combustionin said second combustion means of the fuel in said exhaust with thecompressed air providing a working fluid for said turbine means and fordischarge from said exhaust opening to produce jet thrust for saidIvehicle.

7. A compound power unit as defined in claim 6 wherein said fuel supplyis liquid hydrogen and said oxidant supply is liquid oxygen, saidfuel-rich exhaust being discharged from said engine in the gaseous phaseso that said second combustion means combusts hydrogen gas withcompressed air.

8. A compound power unit for propelling an aircraft comprising a casingdefining a through fluid passage having an exhaust opening, compressormeans located within said casing for compressing atmospheric airentering said casing, a non-air breathing engine located within saidcasing and connected to said compressor means for continually drivingsaid compressor means, a supply of liquid oxygen carried by saidaircraft as the oxidant for said engine, a supply of liquid hydrogencarried by said aircraft as the fuel for said engine, said enginecomprising combustion chamber means receiving oxygen from the oxidantsupply and hydrogen from the fuel supply and turbine expansion means forproducing the shaft power output of said engine, said combustion chambermeans receiving an excess of hydrogen so that the exhaust from saidengine contains a quantity `of hydrogen fuel, turbine means located insaid casing downstream of said compressor means and connected with saidcompressor means, second combustion chamber means located in said casingbetween said compressor means and said turbine means, and means forconnecting said exhaust with said second combustion chamber means sothat fuel in said exhaust can be combusted with compressed air withinsaid second combustion chamber means to provide a working fluid for saidturbine means.

9. A compound power unit for propelling an aircraft comprising a casingdefining a iiuid passage having an exhaust opening, compressor meanslocated in said casing for compressing air entering said passage,turbine means connected with said compressor means and locatedrearwardly thereof in said casing, combustion chamber means located insaid fluid passage between said compressor means and turbine means andutilizing compressed air from said compressor means to maintaincombustion therein, an engine located within said casing and having afuel supply and an oxidant supply, said engine being connected to saidcompressor means to continually drive said compressor means duringiiight of said aircraft, the exhaust from said engine containing aquantity of uncombusted fuel, and means for connecting said combustionchamber means with said exhaust to provide a fuel supply for saidcombustion chamber means.

References Cited in the file of this patent UNITED STATES PATENTS664,958 Linde Jan. l, 1901 2,411,552 New Nov. 26, 1946 2,455,845 WellsDec. 7, 1948 2,511,385 Udale June 13, 1950 2,519,624 Ballantyne et al.Aug. 22, 1950 2,531,761 Zucrow NOV. 28, 1950 2,611,239 Briggs Sept. 23,1952 2,620,625 Phaneuf Dec. 9, 1952 2,636,343 Painter Apr. 28, 19532,648,317 Mikulasek et al. Aug. 11, 1953

